Rosy Wertheim was born on February 19, 1888 in Amsterdam and she died on May 27, 1949 in Laren.After receiving a piano certificate from the Dutch Musicians' Society, she studied harmony and counterpoint with Bernard Zweers and Sem Dresden at the Muzieklyceum in Amsterdam. In Paris she studied composition with Louis Aubert and in Vienna with Karl Weigl.In the 1920’s, she taught solfège en piano at the Muzieklyceum in Amsterdam. She was also conductor of a number of children's and women’s choirs, including the choir of the Religious Socialist Union. In 1929 she moved to Paris for six months but eventually stayed for six years and became friends with Elsa Barraine. Her home was a meeting point for composers including Ibert, Jolivet, Honegger, Milhaud and Messiaen. Thereafter she journeyed to Vienna (1935) and New York (1936) and resettled in the Netherlands in 1937. Following World War II, a period in which she was forced into hiding, she fell ill and never composed again. Until her death she taught at the music school in Laren.She became well-known with the art song 'Neutraal' (1914) on a text by François Pauwels. Up to 1929 she composed mainly art songs and choral works. Her years in Paris were the most productive ones in that period she wrote 'Quatuor à cordes' (1933). Her compositions show influences of van Franck, Debussy, Ravel en Stravinsky. 'Trois Morceaux' (1939), for flute and piano, is written in a more sober and harmonically modern language.